Frequencies for first 10,000 rows of prov6430 variable in pos2010 dataset :

  TOTAL PPM |
       TEST |
    VOLUMES |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |     10,000      100.00      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017